18378720 has 72 divisors (see below), whose sum is σ = 62722296. Its totient is φ = 4900608.

The previous prime is 18378713. The next prime is 18378749. The reversal of 18378720 is 2787381.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4942 + ... + 7821.

It is an arithmetic number, because the mean of its divisors is an integer number (871143).

Almost surely, 2^18378720 is an apocalyptic number.

18378720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18378720 is an abundant number, since it is smaller than the sum of its proper divisors (44343576).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18378720 is a wasteful number, since it uses less digits than its factorization.

18378720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12784 (or 12773 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 36.

The square root of 18378720 is about 4287.0409375232. The cubic root of 18378720 is about 263.8994107141.

The spelling of 18378720 in words is "eighteen million, three hundred seventy-eight thousand, seven hundred twenty".